Parallel tuning of semi‐dwarfism via differential splicing of Brachytic1 in commercial maize and smallholder sorghum

• DOI: 10.1111/nph.19273
• Publication Date: 2023-09-22T09:04:39Z
• Authors: Shuping Jiao; Sujan Mamidi; Mark A. Chamberlin; Mary Beatty; Shawn Thatcher; Kevin D. Simcox; Fanna Maina; Hu Wang‐Nan; Gurmukh S. Johal; Lynn Heetland; Sandeep R. Marla; Robert B. Meeley; Jeremy Schmutz; Geoffrey P. Morris; Dilbag S. Multani
• Keywords: Dwarfism; Germ plasm

In the current genomic era, search and deployment of new semi-dwarf alleles have continued to develop better plant types in all cereals. We characterized an agronomically optimal mutation Zea mays L. a parallel polymorphism Sorghum bicolor cloned maize brachytic1 (br1-Mu) allele by modified PCR-based Sequence Amplified Insertion Flanking Fragment (SAIFF) approach. Histology RNA-Seq elucidated mechanism semi-dwarfism. GWAS linked sorghum height QTL with Br1 homolog resequencing West African landraces panel. The br1-Mu encodes MYB transcription factor78 that positively regulates stalk cell elongation interacting polar auxin pathway. Semi-dwarfism is due differential splicing low functional wild-type transcript expression. ortholog, SbBr1, co-segregates major qHT7.1 alternatively spliced. high frequency Sbbr1 suggests smallholder farmers used improve long before efforts introduce Green Revolution-style varieties 1960s. Surprisingly, variants for Brachytic1 were found both commercial sorghum, suggesting tuning architecture across these systems.